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  • 3D vertically-polarised shear wave (Vsv) velocity model of West Antarctic uppermost mantle structure to 200 km depth developed using data from the 2016-2018 UK Antarctic Seismic Network (UKANET) and Polar Earth Observing Seismic Network (POLENET). The model was constructed from the combination of fundamental mode Rayleigh wave phase velocity maps developed by ambient noise (periods 8-25 seconds) and earthquake data two-plane wave analysis (periods 20-143 seconds). Composite ''local'' 1D Rayleigh wave phase velocity dispersion curves (periods 8-143 s) were extracted by sampling the 2D Rayleigh wave phase velocity maps at grid node locations spanning West Antarctica spaced at 100 km. The local 1D Rayleigh wave phase velocity dispersion curves were inverted for 1D shear wave (Vsv) structure to 200 km depth, and the ensemble of 1D shear wave (Vsv) profiles were subsequently gridded to produce the 3D shear wave (Vsv) model of West Antarctica uppermost mantle structure to 200 km depth. Funding was provided by the NERC standard grant NE/L006065/1.

  • The dataset presented here contains a csv-file including the coordinates, received power of the bed reflection and the two-way travel time of the bed reflection. The X and Y coordinates are projected in EPSG:3031 - WGS 84 / Antarctic Polar Stereographic coordinate system. Data presented here have been frequency filtered and 2D migrated (using a finite difference approach and migration velocity of 0.168 m ns-1), followed by the picking of the bed reflection using ReflexW software (Sandmeier Scientific Software). The received power is calculated within a 280 ns time window centred on, and encompassing, the bed reflection (Gades et al., 2000). This work was funded within the BEAMISH project by NERC AFI award numbers NE/G014159/1 and NE/G013187/1.

  • This dataset provides a 308 year (1703-2010) annual snow accumulation record from the Ferrigno 2010 (F10) ice core. The 136 m core was drilled on the Bryan Coast in Ellsworth Land, West Antarctica, during the austral summer 2010/11. The record was measured using the summer peak in nonsea-salt (nss) SO4, in approximately January to December. Snow accumulation is converted to meters of water equivalent (weq - m) based on measured density profile and correcting for thinning using the Nye model, assuming vertical strain rate. Samples were measured at 5 cm resolution, corresponding to approximately eight samples per year. Funding was provided by the NERC grant NE/J020710/1.

  • 3D vertically-polarised shear wave (Vsv) velocity model of West Antarctic crustal structure developed using data from the 2016-2018 UK Antarctic Seismic Network (UKANET) and Polar Earth Observing Seismic Network (POLENET). Interstation Rayleigh and Love wave phase velocity dispersion measurements at periods of 8-25 seconds were extracted from seismic ambient noise cross-correlograms by automated frequency-time analysis (AFTAN). The ensemble of interstation Rayleigh wave dispersion measurements was used to develop 2D Rayleigh wave phase velocity maps of West Antarctica at periods of 8-25 seconds by Fast Marching Surface Tomography (FMST) on a grid with a node spacing of 0.75deg. ''Local'' 1D Rayleigh wave phase velocity dispersion curves were extracted by sampling the 2D Rayleigh wave phase velocity maps at grid node locations. The local 1D Rayleigh wave phase velocity dispersion curves were inverted for 1D shear wave (Vsv) structure to 40 km depth, and the ensemble of 1D shear wave (Vsv) profiles were subsequently gridded to produce the 3D shear wave (Vsv) model of West Antarctica from 10-40 km depth. Funding was provided by the NERC standard grant NE/L006065/1.

  • This dataset provides a 308 year (1702-2009) deuterium isotope record from the Ferrigno 2010 (F10) ice core. The core was drilled on the Bryan Coast in Ellsworth Land, West Antarctica, during the austral summer 2010/11. The record was measured using a Los Gatos Liquid Water Isotope Analyser at 5cm resolution, corresponding to ~14 samples per year, with annual averages calculated for January-December. Funding was provided by the NERC grant NE/J020710/1

  • This dataset is an estimate of sub ice shelf bathymetry beneath the Thwaites, Crosson and Dotson ice shelves. The output bathymetry is derived from a new compilation of gravity data collected up to the end of the 2018/19 field season. The input gravity dataset includes airborne data from Operation Ice Bridge (OIB) and the NERC/NSF International Thwaites Glacier Collaboration (ITGC), and marine gravity from the R/V Nathaniel B. Palmer cruise NBP19-02. The recovered bathymetry was constrained by swath bathymetry and onshore airborne radio-echo depth sounding data in the surrounding area. Ice shelves mask the critical link between the ocean and cryosphere systems, and hence accurate sub ice shelf bathymetry is critical for generating reliable models of future ice sheet change. Included in the data release is the input free air gravity data, constraining bathymetry/sub-ice topography, and output gravity derived bathymetry. This work was funded by the British Antarctic Survey core program (Geology and Geophysics team), in support of the joint Natural Environment Research Council (NERC)/ National Science Foundation (NSF) International Thwaites Glacier Collaboration (ITGC). Additional specific support came from NERC Grants: NE/S006664/1 and NE/S006419/1, and NSF Grants: NSF1842064, NSFPLR-NERC-1738942, NSFPLR-NERC-1738992 and NSFPLR-NERC-1739003.

  • Point data measurements of ice surface, ice base and lake bed elevation are given from Subglacial Lake Ellsworth (SLE), West Antarctica. The data were acquired during the austral summer of 2007-2008. Five seismic reflection lines were acquired over SLE, with surface elevation determined by dual frequency GPS. Funding was provided by NERC AFI, award numbers NE/D009200/1, NE/D008638/1 and NE/D008751/1. Logistics support: British Antarctic Survey. Equipment support: NERC Geophysical Equipment Facility (loan numbers 838 and 870).

  • This dataset provides a 308 year record of methansulphonic acid (MSA) from coastal West Antarctica, representing sea ice conditions in the Amundsen-Ross Sea. Annual average MSA has been calculated from the 136 m Ferrigno ice core (F10), drilled on the Bryan Coast in Ellsworth Land, West Antarctica during the austral summer 2010/11. The sea ice extent is based on geometric mean regression of MSA flux with satellite sea ice extent from 146 degrees west. The record was measured using a Dionex ICS2500 anion system at 5 cm resolution, corresponding to approximately 14 samples a year. Funding was provided by the NERC grant NE/J020710/1.

  • We present here the airborne Lidar data was collected over the Thwaites Glacier catchment and adjacent ice shelves during the 2018/19 and 2019/20 field seasons. The data was collected using a Riegl Q240i-80 scanning system mounted in the BAS aerogeophysically equipped twin otter aircraft. It provides a high resolution (0.2 to 0.4 points per m2), and high accuracy (~10 cm vertical) georeferenced and time stamped swath of surface elevation information. Each track is ~600 m wide. Such data provides critical information about how the surface of the Thwaites Glacier system is changing. The Thwaites 2019/20 aerogeophysical survey was carried out as part of the BAS National Capability contribution to the NERC/NSF International Thwaites Glacier Collaboration (ITGC) program, with additional funding for LIDAR data processing from the UK Foreign and Commonwealth Office.

  • This dataset contains an ASCII file with shear wave splitting results for 202,651 station-event pairs from glacial micro-seismicity, recorded from a 35-station seismic network located ~40 km upstream of the grounding line of Rutford Ice Stream, West Antarctica. Microseismicity is located at the base of the ice stream at ~2.2 km depth (relative to the ice surface). Seismic waveform data, which was used to calculate shear wave splitting parameters is provided in miniseed format. Event hypocenter information, event times and coordinates of receiving stations are listed in the ASCII file. Shear wave splitting was calculated using the software MFAST. Shear wave splitting parameters can be used to determine seismic anisotropy along the ray path, which helps to characterise ice fabric. This work was funded within the BEAMISH project by NERC AFI award numbers NE/G014159/1 and NE/G013187/1. Seismic instruments were provided by NERC SEIS-UK (Loan 1017) and the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center at New Mexico Tech.